Always been curious of when the first CBA came about.
From this FAQ:
Bob Cousy began to organize the NBA players in 1954, although the league refused to recognize the union until 1957. A near strike at the 1964 All-Star game forced the league to adopt a pension plan. The first CBA was established in 1970, and new agreements followed in 1973, 1976 and 1980. The 1976 CBA coincided with the settlement of the "Oscar Robertson" suit, which was filed by the players association in 1970 to block the NBA-ABA merger. The 1976 agreement also provided limited free agency through the elimination of "option" clauses that bound players to teams in perpetuity.
From another account:
COUSY ORGANIZES THE PLAYERS
Economic conditions continued unchanged through 1954, at which point Bob Cousy, the league's top player, began to organize the NBPA, which would become the first team sports player's union. Cousy began by writing to an established player from each of the league's teams (Paul Arizin of Philadelphia, Carl Braun of New York, Bob Davies of Rochester, Paul Hoffman of Baltimore, Andy Phillip of Fort Wayne, Pollard, Dolph Schayes of Syracuse and Don Sunderlage of Milwaukee) in hopes of encouraging solidarity among the players. All but Phillip responded positively (of all the owners, Fort Wayne's Fred Zollner, who owned a machine works plant, was the staunchest union opponent and this prevented the Pistons players from participating), and Cousy next went to NBA President Maurice Podoloff at the January, 1955 NBA All-Star Game with a list of concerns: payment of back salaries to the members of the defunct Baltimore Bullets club; establishment of a twenty-game limit on exhibition games, after which the players should share in the profits; abolition of the $15 "whispering fine" which referees could impose on a player during a game; payment of $25 expenses for public appearances other than radio, television or certain charitable functions; establishment of an impartial board of arbitration to settle player-owner disputes; moving expenses for traded players; and payment of player salaries in ten installments rather that twelve, to provide more money to players cut during the season. Podoloff agreed to the payment of two weeks' salary to six players who had played for Baltimore before the franchise folded and committed to meeting with the player representatives within two weeks over their concerns.
As the excerpts above show, players were unhappy with the financial arrangements that they had with the NBA. The players wanted a better pension, some control over the "whisper" fines that referees could impose, payment of back salaries to certain players, and to settle other working conditions and payments.